1. School of Chemical Engineering and TechnologyTianjin University Yaguan Road 135 Tianjin 300350 P. R. China
2. Shenzhen Engineering Laboratory of Phosphorene and OptoelectronicsKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Optoelectronic EngineeringShenzhen University Shenzhen 518060 P. R. China
3. School of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai University Tongyan Road 38 Tianjin 300350 P. R. China